docs: def confirm_delivery(self, delivery_tag, delivered):
          """Invoked by RabbitMQ when it is confirming delivery via a Basic.Ack
  
          :param
          :param int delivery_tag: The message # being confirmed
          :param bool delivered: Was the message delivered
  
          """
          for offset, msg in self.pending_confirmations():
              if delivery_tag == msg.delivery_tag:
                  self.published_messages[offset].future.set_result(delivered)
                  return
          for msg in self.published_messages:
              if msg.delivery_tag == delivery_tag and msg.future.done():
                  return
          self.logger.warning('Attempted to confirm publish without future: %r',
                              delivery_tag)